Croissance et cycle des voies génitales femelles de Typhlonectes compressicaudus (Duméril et Bibron, 1841), amphibien apode vivipare

Abstract

In Typhlonectes compressicaudus the female genital ducts consist of an oviduct and a uterus. A longitudinal groove runs parallel to the oviduct, instead of a funnel. It's only during the second year after birth that modifications in genital ducts prepare the reproductive cycle. In female adults, funnel and oviduct are provided with cilia as early as October. Glands are developing at the level of the oviduct in which we observe 3 types of cells. After the ovulation (at the end of April), these structures set in rest again. From October to December we observe the development of the uterine wall in which are found also three types of cells, provided with cilia or glandular secretions. In pregnant females, this uterine wall undergoes modifications which are linked to the stages of the embryo's development. From July to October (after parturition) the uterus set in rest again; it's the same for the females without ovulation. Structural modifications of the female genital ducts are linked to the evolution and biennial cycle of the ovary at the level of which we detect steroidogenic activity.

Stages in spermatogenesis of two species of caecilians, Ichthyophis tricolor and Uraeotyphlus cf. narayani (Amphibia: Gymnophiona): Light and electron microscopic study

“…Exbrayat and Sentis (1982) and Exbrayat (1986a) examined the annual testicular cycle of Typhlonectes compressicaudus. De Sa and Berois (1986) described the spermatogenesis of Chthnonerpeton indistinctum.…”

“…Seshachar (1936) described six stages in male germ cell development: primary spermatogonia, secondary spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, and sperm in Ichthyophis glutinosus. Exbrayat and Sentis (1982), in their report on the annual reproductive cycle in Typhlonectes compressicauda, identified isogenic series of germ cells as primary spermatogonia, secondary spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, young sperm, sperm, and free sperm. All these observations are based on a light microscopic perspective.…”

Secretory and basal cells of the epithelium of the tubular glands in the male Mullerian gland of the caecilian Uraeotyphlus narayani (Amphibia: Gymnophiona)

“…Caecilians (Amphibia: Gymnophiona) are unique among the vertebrates in that they retain the Mullerian duct, the progenitor of the female oviduct, in the adult male as a functional gland, the Mullerian gland (Mü ller, 1831;Tonutti, 1931;Wake, 1970Wake, , 1977aWake, ,b, 1981Exbrayat, 1985Exbrayat, , 1986Exbrayat, , 1992. The Mullerian gland is formed from a large number of tubular glands lined by an epithelium arranged around the circumference of a central Mullerian duct (Wake, 1970(Wake, , 1977a(Wake, ,b, 1981Exbrayat, 1985Exbrayat, , 1986Exbrayat, , 1992.…”

“…The Mullerian gland is formed from a large number of tubular glands lined by an epithelium arranged around the circumference of a central Mullerian duct (Wake, 1970(Wake, , 1977a(Wake, ,b, 1981Exbrayat, 1985Exbrayat, , 1986Exbrayat, , 1992. We have recently shown that in Uraeotyphlus narayani a distinct duct connects each of the tubular glands to the central Mullerian duct (George et al, 2004).…”

“…It has been hypothesized, based on indirect evidence, that the Mullerian gland could be the evolutionary predecessor of the prostate gland of mammals and, thus, its secretory material would be comparable to the seminal plasma in which sperm are suspended during ejaculation in mammals (Tonutti, 1931;Wake, 1970Wake, , 1981Exbrayat, 1985). However, to date there is no report of the cellular mechanism of formation of the secretory material in the epithelial cells of the tubular glands.…”